/*
  KeePass Password Safe - The Open-Source Password Manager
  Copyright (C) 2003-2013 Dominik Reichl <dominik.reichl@t-online.de>

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

using System;
using System.Collections.Generic;
using System.IO;
using System.Drawing;

using KeePassLib;
using KeePassLib.Interfaces;

namespace KeePass.DataExchange
{
  public abstract class FileFormatProvider
  {
    public abstract bool SupportsImport { get; }
    public abstract bool SupportsExport { get; }

    public abstract string FormatName { get; }

    public virtual string DisplayName
    {
      get { return this.FormatName; }
    }

    /// <summary>
    /// Default file name extension, without leading dot.
    /// If there are multiple default/equivalent extensions
    /// (like e.g. "html" and "htm"), specify all of them
    /// separated by a '|' (e.g. "html|htm").
    /// </summary>
    public virtual string DefaultExtension
    {
      get { return string.Empty; }
    }


    public virtual bool RequiresFile
    {
      get { return true; }
    }

    public virtual bool SupportsUuids
    {
      get { return false; }
    }

    public virtual bool RequiresKey
    {
      get { return false; }
    }

    /// <summary>
    /// This property specifies if entries are only appended to the
    /// end of the root group. This is true for example if the
    /// file format doesn't support groups (i.e. no hierarchy).
    /// </summary>
    public virtual bool ImportAppendsToRootGroupOnly
    {
      get { return false; }
    }



    /// <summary>
    /// Called before the <c>Export</c> method is invoked.
    /// </summary>
    /// <returns>Returns <c>true</c>, if the <c>Export</c> method
    /// can be invoked. If it returns <c>false</c>, something has
    /// failed and the export process should be aborted.</returns>
    public virtual bool TryBeginExport()
    {
      return true;
    }

    /// <summary>
    /// Import a stream into a database. Throws an exception if an error
    /// occurs. Do not call the base class method when overriding it.
    /// </summary>
    /// <param name="pwStorage">Data storage into which the data will be imported.</param>
    /// <param name="sInput">Input stream to read the data from.</param>
    /// <param name="slLogger">Status logger. May be <c>null</c>.</param>
    public abstract void Import(PwDatabase pwStorage, Stream sInput,
                                IStatusLogger slLogger);
    /// <summary>
    /// Export data into a stream. Throws an exception if an error
    /// occurs (like writing to stream fails, etc.). Returns <c>true</c>,
    /// if the export was successful.
    /// </summary>
    /// <param name="pwExportInfo">Contains the data source and detailed
    /// information about which entries should be exported.</param>
    /// <param name="sOutput">Output stream to write the data to.</param>
    /// <param name="slLogger">Status logger. May be <c>null</c>.</param>
    /// <returns>Returns <c>false</c>, if the user has aborted the export
    /// process (like clicking Cancel in an additional export settings
    /// dialog).</returns>
    public virtual bool Export(PwExportInfo pwExportInfo, Stream sOutput,
        IStatusLogger slLogger)
    {
      throw new NotSupportedException();
    }
  }
}
